Merge pull request #11 from Tuxle/development

Participant needed an explicit constructor.
renamed the constructor argument, so that it has the same name as the instance variable ("one thing, one name" or something like that).
added a first 'draft' of ecc. Probably the implementation gets changed again.
cleanup of the RSA files.
added the sha-256 digest since this is neede for message integrity checks.
deleted the CipherSuite because it's acutally not really necessary. probably it can be left away always.
updated the cipher and key generator for clearer interface. now the bouncy castle api is directly used.
added code coverage plugin to the maven project. after that, added a few trivial tests to cover the rest (what was easily possible and made (at least a little) sense).
also cleaned up.